JPH03193968A - Device for measuring thickness and irregularity of sliver - Google Patents

Abstract

PURPOSE: To obtain the subject device capable of certifying a sufficient measurement accuracy even at a high speed without hard depositing impurities contained in the sliver by disposing cooling systems in a compression member comprising a pair of rollers for sensing the thickness of the sliver. CONSTITUTION: In a compression member comprising a pair of stepped hollow rollers 5 for compressing a sliver and for sensing the thickness of the sliver, cooling systems 11, 12, 13 for cooling the rollers with a cooling agent (preferably, air) are disposed in a circulation route wherein the cooling agent L is charged from a cooling connection portion 11 disposed in the center of at least one of the pair of hollow stepped rollers 5 into the cavity 12 of the roller, allowed to flow in the cavity along the inner surface of the roller by the rotation of the roller, and then discharged from openings 13 on the outside. Thereby, it can be prevented that fine impurities discharged from the sliver by the compression of the sliver are hard deposited on the surfaces of the rollers, and the signal of an accurate sliver cross-sectional thickness sensed by the pair of rollers 5 can be inputted into an electronic controller 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for measuring the thickness and unevenness of a sliver, which has a member for compressing the sliver.

[Conventional technology]

This type of equipment is used to control the weight of the sliver on the cotton sliver or filament machine, and to keep the so-called number fluctuations in the system small so as not to disturb the finished product. It is used in systems that The main difference in known control systems lies in the measurement system. There are basically three types of such measurement systems known. namely, so-called dynamic pneumatic measuring systems, roller measuring systems and fiber compaction systems. For the first two measurement systems, reference is made to Worcester News Plate No. 30. June 1982, and for the last system, reference is made to US Patent Application Publication No. 864,853. What these systems have in common is that the thickness of the sliver is measured on a compressed sliver, either by providing a special compression element or by compressing the sliver with the measuring element itself.

In roller measuring systems, the compression of the sliver is carried out on the measuring roller itself, which is formed by a pair of rollers, between the pairs of rollers. In order to prevent the sliver from coming off laterally from the grip between the rollers, the two rollers overlap each other,
In particular, stepped rollers or so-called grooved roller designs are used. When this type of roller system is used in a straightening machine, the sliver passes through the machine faster than in a straightening machine, so that at high speeds approaching 1000 m/min, the measurement accuracy can no longer be guaranteed. It has been discovered.

Actual research has shown that the cause of this is dirt on the measuring roller. During compression of the sliver, the air in the sliver is compressed and rapidly pushed out of the sliver,
At the same time, it carries out minute impurities contained in the sliver,
This is deposited on the roller surface. The faster the sliver passes, the more air is compressed per unit time, and the more minute impurities are carried by it. This includes, for example, organic matter covered with honeydew, such as seed pieces, lumps, and short fibers.

It has been shown that contamination can occur even at low sliver speeds, but this can be removed mechanically without problems. However, at such high speeds, conventional methods of mechanically cleaning the rollers have proven ineffective. Cleaning using conventional methods is not fully effective. That is, the rollers are not truly clean.

[Problem to be solved by the invention]

The aim of the invention is to improve the known device and to provide a device in which the above-mentioned undesirable effects no longer occur and in which sufficient measuring accuracy is guaranteed even at high speeds.

[Means to solve the problem]

This object is achieved according to the invention in that the compression element has a cooling system.

According to the invention, the arrangement of the cooling system of the compression element, which is arranged on one of the compression elements, for example the roller of a roller measuring system, produces an unexpected effect, an effect that surprises even experts in the field. Once produced and cooled, the roller can be cleaned using conventional methods and the measurements are extremely stable and reproducible. Thus,
Even with roller measuring systems, the sliver speed is 1/min.
For the first time, it is possible to operate at distances of 1,000 m or more without affecting measurement accuracy or losing the meaning of measurement.

The above-mentioned surprising effect is due to the following fact.

That is, due to cooling, contamination is less likely to occur. Without cooling, the honeydew-covered microscopic impurities coming out of the sliver will stick to the roller surface and become baked onto the roller under the effect of high roller temperature, thus making it very difficult to remove mechanically. A hard layer forms. The formation of this layer can actually be prevented by using a cooling system.

〔Example〕 The details of the present invention will be explained below using the accompanying figures.

As is well known, the drafting system shown in FIG. Proceed in direction A. By choosing appropriate speeds, it is possible to set the brake draft between roller pairs l and 2 and the main draft between roller pairs 2 and 3. The fleece 4 passing through the drafting system is collected into a sliver by a trumpet (not shown). The sliver is then compressed by a pair of stepped rollers 5, and the compressed sliver 6 is finally fed via a coiler roller 7 to a can 8.

The cross-sectional thickness of the spun sliver 6 is sensed by a pair of stepped rollers 5, and a corresponding cross-sectional thickness signal is supplied to an electronic control unit 9. The control wave [9 processes the cross-section thickness signal to form a suitable control signal, which control signal is applied to a variable speed drive 10, preferably a DC motor, and the drive 1o is applied to the two rollers 2. control. This control method is not fundamentally important to the present invention, and known methods can be used. In this regard, FIG. 2 shows a cross-section of the stepped roller pair 5. A measuring element similar to the stepped roller is the grooved roller measuring element, also called tank and group. In these, the edges of one roller overlap the other roller in a 0-shape. In both systems, these rollers, of diameter not exceeding a certain maximum value, are driven at very high speeds and the power required to compress the fleece generates high temperatures at the rollers. That is, power is converted into heat.

Fleece also contains a large number of fine particles of organic impurities and inclusions coated with sticky substances, such as honeydew. These particles are the air in the sliver that is forced out during compression of the sliver, and are ejected out of the sliver and reach the heated roller surface at high speed, where they are deposited, melt, and become a well-ordered mass with an outer shell. As a result, the cross-sectional thickness signal supplied from the roller pair no longer represents the cross-sectional thickness and becomes meaningless.

As shown in FIG. 2, at least one roller of the Ronilla pair 5 is provided with a cooling system. The cooling system prevents the roller fouling mentioned above, as shown in real tests.
Or at least significantly reduce it. This cooling system has a hollow structure in which the roller has a central cooling connection 11 through which coolant L1, preferably air, can be introduced into the roller cavity 12. As the roller rotates, air flows radially outward inside the cavity along the inner surface of the roller and is finally forced out of the roller through the apertures 13. During this circular movement, the air cools the rollers.

The dimensions and design of the cooling system are determined by specific practical requirements, and practical experience shows that fouling of the rollers is largely prevented at temperatures below 80°C, preferably kept at about 60°C. . Further, cooling is achieved by supplying air continuously or intermittently from the connecting portion 11. Alternatively, a valve controlled by a temperature sensor can be used at connection 1.
It can also be provided in the pipe path leading to 1.

The description of the cooling system according to the invention in connection with a roller measurement system as described above should not be construed as limiting. Conversely, a cooling system of this type can also be used for compressing and/or measuring elements for other fiber aggregates or slivers.

The present cooling system is not limited to the embodiments used in the description, but can take many forms. It is thus possible, for example, to attach a fan or other suitable cooling element directly to the measuring roller.

4

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a wire forming machine with an autoleveler, and FIG. 2 is a sectional view of a stepped roller measuring element of the wire forming machine with an autoleveler shown in FIG.

Claims (1)

[Scope of Claims] 1. A device for measuring the thickness and unevenness of a sliver, which includes a member for compressing a sliver, wherein the compression member (5
Device for measuring the thickness and unevenness of a sliver, characterized in that the device (11, 12, 13) has a cooling system (11, 12, 13). 2. Device according to claim 1, characterized in that the member (5) consists of a pair of rollers, at least one of the two rollers (5) having a connection to the coolant (L). 3. Device according to claim 2, characterized in that the roller (5) is designed as a hollow roller and has a compressed air connection (11) and an air outlet opening (13). 4. Device according to claim 3, characterized in that the compressed air connection (11) is provided in the region of the rotation axis and the air outlet opening (13) is provided in the periphery of the roller (5). 5 The rotation axis of the roller (5) is located in the cavity (12) of the roller.
5. Device according to claim 4, characterized in that it consists of a pipe with an opening in it, ensuring circulation of air from the pipe through the cavity to the air outlet opening (13). 6. Device according to claim 5, characterized in that air is continuously supplied to the compressed air connection (11). 7. Device according to claim 5, characterized in that air is supplied intermittently to the compressed air connection (11). 8. Device according to claim 5, characterized in that upstream of the compressed air connection (11) there is provided a valve for controlling and regulating the supply of compressed air. 9 The cooling system (11, 12, 13)
9. The device according to claim 2, wherein the device is designed such that the temperature of the roller surface in contact with the roller does not exceed 80°C.